Question:
When potassium dichromate crystals are heated, we get
When potassium dichromate crystals are heated, we get
Updated On: Jun 23, 2023
- oxygen
- hydrogen
- sulphur dioxide
- hydrogen sulphide
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The Correct Option is A
Solution and Explanation
Potassium dichromate, on heating, gives oxygen and green chromic oxide $\left( Cr _{2} O _{3}\right)$ vapour.
$4 K _{2} Cr _{2} O _{7} {->[\Delta]} 4 K _{2} CrO _{4}+\underset{\text { green }}{2 Cr _{2} O _{3} \uparrow}+3 O _{2} \uparrow$
Though ammonium dichromate, on heating gives nitrogen gas.
$\left( NH _{4}\right)_{2} Cr _{2} O _{7} {->[\Delta]} N _{2}+ Cr _{2} O _{3}+4 H _{2} O$
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Concepts Used:
Some Basic Concepts of Chemistry
Chemistry is a vast subject and for understanding its significance we can take help of following points:
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- Chemistry is important in order to understand the behaviour of fertilizers, alkenes, acids, salts, dyes, polymers, drugs, soaps and alloys in organic and inorganic chemistry.
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Classification of Matter
There are two ways of classifying the matter:
(A) Physical Classification:
Matter can exist in three physical states:
- Solids - have definite volume and definite shape
- Liquids - have definite volume but not definite shape.
- Gases - have neither definite volume nor definite shape.
(B) Chemical Classification:
Based upon the composition, matter can be divided into two main types:
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